import java.awt.*;
import java.io.*;
import java.net.*;
public class URLAccessTest {
  static void displayInfo(URLConnection u)
    throws IOException
  {
    URL url = u.getURL();
    println(url.toExternalForm() + ": ");
    println("Type: ", u.getContentType());
    println("Length: ", u.getContentLength());
    println("Modified: ",
      new Date(u.getLastModified()));
    println("Expires: ", u.getExpiration());
    println("Encoding: ",
      u.getContentEncoding());
    
      DataInputStream in = u.getInputStream();
    String line;
    while ((line = in.readLine()) != null)
      println(line);
  }
  public static void main(String[] args)
    throws IOException
  {
    URL url = new URL(argv[0], argv[1]);
    try
      displayInfo(url.openConnection());
    catch (Exception E) {}
    
  }
}

import java.awt.*;
import java.io.*;
import java.net.*;
class P {
  static final int PORT = 2346;
  static final String HOST = "ics.uci.edu";
}
public class SimpleServer {
  public static void main(String[] args)
  {
    Server serv = new Server(P.PORT);
    serv.out.println("Send me a string:");
    try {
      String data = serv.in.readLine();
      println("Client says: " + data);
    }
    catch (IOException e) {}
  }
}
class Server {
  Socket chan;
  DataInputStream in;
  PrintStream out;
  ServerSocket server;
  Server(int port)
  {
    try {
      server = new ServerSocket(port);
      chan = server.accept();
      out = new PrintStream(chan.getOutputStream());
      in = new DataInputStream(chan.getInputStream());
    }
    catch (IOException e) {}
  }
}

import java.awt.*;
import java.io.*;
import java.net.*;
public class SimpleClient {
  public static void main(String[] args)
  {
    Client s = new Client(P.HOST, P.PORT);
    String msg;
    try {
      msg = s.in.readLine();
      println("Server says: " + msg);
    }
    catch (IOException e) {}
    s.out.println("Recieved: " + msg);
  }
}
class Client {
  DataInputStream in;
  PrintStream out;
  Socket s;
  public Client(String host, int port)
  {
    try {
      s = new Socket(host, port);
      out = new PrintStream(s.getOutputStream());
      in = new DataInputStream(s.getInputStream());
    }
    catch (IOException e) {System.out.println(e);}
  }
}

class DP {
  static final int PORT = 2345;
}
public class Sender {
  public static void main(String args[])
    throws Exception
  {
    InetAddress addr = InetAddress.getByName(args[0]);
    int msglen = args[1].length();
    byte[] msg = new byte[msglen];
    args[1].getBytes(0, msglen, msg, 0);
    DatagramPacket packet =
       new DatagramPacket(msg, msglen, addr, DP.PORT);
    DatagramSocket socket = new DatagramSocket();
    socket.send(packet);
  }
}

public class Receiver {
  byte[] buffer = new byte[1024];
  DatagramPacket p = new DatagramPacket(buffer, buffer.length);
  DatagramSocket socket = new DatagramSocket(DP.PORT);
  while (true)
  {
    socket.receive(packet);
    String s = new String(buffer, 0, 0, packet.getLength());
    System.out.println("Received from " 
      + packet.getAddress().getHostName()
      + packet.getPort());
    System.out.println(s);
  }
}